Fig. 1

Orthotopic HCC development induces a pre-metastatic niche in the lung. (A-B) Pulmonary metastasis was not observed 2 weeks after orthotopic Hepa1-6- implantation or 1 week after orthotopic H22 implantation. (A) Detection of pulmonary metastasis 2 weeks after orthotopic implantation of matrigel or Hepa1-6 cells (upper) and 1 week after orthotopic implantation of matrigel or H22 cells (lower) in the liver by H&E staining. Scale bar, 100 μm. (B) Detection of luc2 by qPCR in the lung of mice 2 weeks after orthotopic implantation of matrigel or Hepa1-6 cells in the liver. (C) Schematic for the procedures of Hepa1-6 and H22 xenograft mouse models. Or., orthotopic implantation. (D-E) Increased numbers of myeloid cells and inflammatory cells in the pre-metastatic lung of orthotopic HCC xenografts. IHC staining (D) and flow cytometry analysis (E) of CD11b⁺, Ly6G⁺ and S100A9⁺ cells in the lung of mice 2 weeks after orthotopic implantation of Hepa1-6 cells in the liver. Scale bar, 25 μm. (F-G) IHC staining (F) and flow cytometry analysis (G) of CD11b⁺, Ly6G⁺ and S100A9⁺ cells in the lung of mice 1 week after orthotopic implantation of H22 cells. Data are displayed as the mean ± SEM; unpaired Student’s t test (B, D, E). **, P < 0.01; ***, P < 0.001; ****, P < 0.0001; ns, not significant